Trade Station Strategies

Simple and Effective Strategies

39+40 XCAP IpolyFit

This indicator provides as output the least square best fit to a set of polynomials of maximum power (degree) using
discrete Legendre polynomials. This is accomplished by decomposing the time series into discrete Legendre polynomials
over the interval of orthogonality given by 2 * Width + 1 and discarding the polynomial fits degrees above some maximum degree.
The remaining smoothed series,

SmoothedSeries[t] = c[0] * 1 + c[1] * (t-Width) + c[2] * Power(t-Width,2) + … c[MaximumDegree]*Power(t-Width,MaximumDegree)

has coefficients given by the array c that are determined such that this polynomial has the minimum least square error over
the interval. The indicator provides two outputs:

ShowLeadingEdge = TRUE

As you move forward along the time series, the fit is generated. What is displayed is the leading, rightmost bar, “[0]”, for
each fit. This is also obtainable via the Savitzky Golay method, see the reference 3 below.

ShowLastFit = TRUE

This displays the entire last fit for just the last bar on the chart, so you will only see an output on the last
2*Width + 1 bars of your chart.